Hello Robert,
* Robert Watson <rwatson@FreeBSD.org> wrote:
> On Sat, 23 Aug 2008, Ed Schouten wrote:
>
>> Remove old BSD-style entries from /etc/ttys and increase pts(4) to 512.
>>
>> Because we now use pts(4)-style PTY's exclusively, there is no use for
>> these entries in /etc/ttys. Right now the pts(4) entries only go from 0
>> to 255. Because we're going to touch these files anyway, increase the
>> number to 511.
>
> Won't older pty-using binaries from 4.x/5.x/6.x/7.x running with compat
> parts or old library versions still use old-style ptys, and hence need
> them in /etc/ttys?
It really depends on what your definition of "need" is in this case. The
reason why PTY's are listed in /etc/ttys, is to store login entries in
/var/run/utmp. This means lastlog and wtmp are not affected.
There is no need for an entry in /etc/ttys to be able to use a TTY and
there is no guarantee an application using PTY's actually logs its usage
in any logfile.
The reason why I chose to remove the old devices and add some additional
lines for pts(4), was because I was looking at a typical setup. The
previous /etc/ttys was quite broken in two ways:
- It contained 512 entries for a PTY naming scheme that (in RFC terms)
SHOULD NOT be used on most common setups.
- It contained 256 entries for a PTY naming scheme that we use right
now.
If we wanted to make everyone happy, I could have just added all pts(4)
entries from 0 to 999, but that would have made /var/run/utmp at least
75 KB, which is a little big in my opinion. Rhis is why I, based on my
expectations of the typical use case, decided to remove the pty(4)
entries and extend the pts(4) ones.
--
Ed Schouten <ed@80386.nl>
WWW: http://80386.nl/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (FreeBSD)
iEYEARECAAYFAkiwhtIACgkQ52SDGA2eCwWnWACfQgca1SMpENKdOx3nK38Wj5V8
dxkAniWa7VYDOzAKDyxg1fTWt0nUA2q0
=aArv
-----END PGP SIGNATURE-----